2016 Volume 56 Issue 8 Pages 1404-1412
A swirling flow has been demonstrated to be beneficial for making the flow pattern even and to reduce turbulence during filling in ingot casting. A new swirling flow generation device, TurboSwirl, was applied to improve the flow pattern of the liquid steel as it flows into the mold so that a more stable flow could be obtained. A water model was built including the TurboSwirl with different flaring angles of the divergent nozzle, according to a former numerical study indicating that a much more beneficial flow pattern could be obtained by reducing the flaring angle. To validate the mathematical model, the air-core vortex formed in the water model experiment was used, and the length of the vortex was measured and compared to the numerical predictions. Different turbulence models including the standard k-ε, realizable k-ε and Reynolds stress model were tested. It was found that only the Reynolds stress model could most accurately simulate the high swirling flow including a vortex. In addition, the radial velocity of the water around the vortex was measured by an ultrasonic velocity profiler (UVP). The experimental results revealed a high turbulence of the swirling flow and strong fluctuations of the vortex. The radial velocity of the water around the upper part of the vortex could be predicted well compared to the experimental results by the UVP measurements.